in china dl.google.com is not available, add flag -m to use china ustc mirror

[SunJary]

usage:
go1.19.1 download -m "ustc"

[google-cla]

Thanks for your pull request! It looks like this may be your first contribution to a Google open source project. Before we can look at your pull request, you'll need to sign a Contributor License Agreement (CLA).

View this failed invocation of the CLA check for more information.

For the most up to date status, view the checks section at the bottom of the pull request.

[gopherbot]

This PR (HEAD: daf2e06) has been imported to Gerrit for code review.

Please visit https://go-review.googlesource.com/c/dl/+/429877 to see it.

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[gopherbot]

Message from Gopher Robot:

Patch Set 1:

Congratulations on opening your first change. Thank you for your contribution!

Next steps:
A maintainer will review your change and provide feedback. See
https://go.dev/doc/contribute#review for more info and tips to get your
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Most changes in the Go project go through a few rounds of revision. This can be
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have a lasting impact.

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Please don’t reply on this GitHub thread. Visit golang.org/cl/429877.
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[gopherbot]

Message from Bryan Mills:

Patch Set 1: Hold+1

(1 comment)

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Please don’t reply on this GitHub thread. Visit golang.org/cl/429877.
After addressing review feedback, remember to publish your drafts!

[gopherbot]

Message from jary sun:

Patch Set 1:

(1 comment)

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After addressing review feedback, remember to publish your drafts!

[gopherbot]

Message from Meng Zhuo:

Patch Set 1:

(1 comment)

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Please don’t reply on this GitHub thread. Visit golang.org/cl/429877.
After addressing review feedback, remember to publish your drafts!

[gopherbot]

Message from jary sun:

Patch Set 1:

(1 comment)

---

Please don’t reply on this GitHub thread. Visit golang.org/cl/429877.
After addressing review feedback, remember to publish your drafts!

[gopherbot]

Message from Gopher Robot:

Patch Set 1:

Congratulations on opening your first change. Thank you for your contribution!

Next steps:
A maintainer will review your change and provide feedback. See
https://go.dev/doc/contribute#review for more info and tips to get your
patch through code review.

Most changes in the Go project go through a few rounds of revision. This can be
surprising to people new to the project. The careful, iterative review process
is our way of helping mentor contributors and ensuring that their contributions
have a lasting impact.

---

Please don’t reply on this GitHub thread. Visit golang.org/cl/429877.
After addressing review feedback, remember to publish your drafts!

[gopherbot]

Message from Bryan Mills:

Patch Set 1: Hold+1

(1 comment)

---

Please don’t reply on this GitHub thread. Visit golang.org/cl/429877.
After addressing review feedback, remember to publish your drafts!

[gopherbot]

Message from jary sun:

Patch Set 1:

(1 comment)

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Please don’t reply on this GitHub thread. Visit golang.org/cl/429877.
After addressing review feedback, remember to publish your drafts!

[gopherbot]

Message from M Zhuo:

Patch Set 1:

(1 comment)

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After addressing review feedback, remember to publish your drafts!

[gopherbot]

Message from jary sun:

Patch Set 1:

(1 comment)

---

Please don’t reply on this GitHub thread. Visit golang.org/cl/429877.
After addressing review feedback, remember to publish your drafts!